feat|fix: generates models and fixes the tests

[nickfloyd]

This PR does two things:

1. Generates the models using the latest schema
2. Fixes the broken tree expression tests - This happened because optional arguments in this context are a feature of C# that doesn't have a direct representation in the expression tree format. So we had to pass all arguments to the expression (when defaults were present)

---

Before the change?

• The tests failed
• The models were out of date

After the change?

• The query tests now run green
• The models have been updated to the latest representation

[github-actions]

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[kfcampbell]

🚀 🚀 🚀